Northfield Mountain
Northfield Mountain is a pumped-storage hydro plant in Franklin County, Massachusetts, operated by FirstLight Power Resources, Inc. - MA. It ranks second by nameplate capacity among Massachusetts’s 685 power plants. Among the 33 pumped-storage plants in the country it is the sixth-largest.
Nameplate capacity, 2025
1,168 MW
1,168 MW net summer capacity
4 operable units
- Pumped-storage hydro1,168 MW100%
Unit by unit, 1972 to 2025
operating in 2025bar height follows unit size
Unit 4 Pumped-storage hydro, 292 MW, 1972
Unit 1 Pumped-storage hydro, 292 MW, 1973
Unit 2 Pumped-storage hydro, 292 MW, 1973
Unit 3 Pumped-storage hydro, 292 MW, 1973
Among Massachusetts’s plants
Largest plants in the state by nameplate capacity, with the plants ranked next to this one.
- 1Canal1,495 MW
- 2Northfield Mountainthis plant
- 3Fore River Generating Station872 MW
- 4Salem Harbor Power Development LP798 MW
Other rankings
- All US power plants
- 239th of 14,286
- Pumped-storage plants in Massachusetts
- 1st of 2
- Plants in the ISO New England balancing area
- 4th of 1,475
- Plants run by FirstLight Power Resources, Inc. - MA
- 1st of 4
- Biggest single unit, among Massachusetts’s plants
- 5th of 685
Operable units
| Unit | Technology | Nameplate | Summer | Online | Status |
|---|---|---|---|---|---|
| 4 | Pumped-storage hydro | 292 MW | 292 MW | 1972 | Operating |
| 1 | Pumped-storage hydro | 292 MW | 292 MW | 1973 | Operating |
| 3 | Pumped-storage hydro | 292 MW | 292 MW | 1973 | Operating |
| 2 | Pumped-storage hydro | 292 MW | 292 MW | 1973 | Operating |
Grid and site
- Balancing area
- ISO New England
- Reliability region
- Northeast Power Coordinating Council
- Highest grid connection voltage
- 345 kV
- Water source
- Connecticut River
- Nearest town on record
- Northfield
- Operator type
- Independent producer
- Coordinates
- 42.611°N, 72.472°W
Closest plants
| Plant | Runs on | Capacity | Distance |
|---|---|---|---|
| NFM Solar Power LLC | Solar | 1.9 MW | 0.1 mi west |
| Erving CSG | Solar | 1 MW | 0.5 mi south |
| French King Solar LLC | Solar | 5 MW | 1.4 mi southwest |
| Kearsarge Gill | Solar | 2 MW | 4.2 mi north |
| Erving Paper Mills | Natural gas | 6.2 MW | 4.4 mi east |
| Turners Falls | Hydroelectric | 5.7 MW | 4.6 mi west |
| Kearsarge Montague BD(CSG) | Solar | 3.8 MW | 4.7 mi west |
| Kearsarge Montague | Solar | 4 MW | 5.0 mi west |